As one example of semiconductor manufacturing, there is available a vertical heat treatment apparatus for thermally treating, e.g., a plurality of semiconductor wafers (hereinafter referred to as wafers) in a batch-wise manner. The vertical heat treatment apparatus is installed in an air atmosphere. The vertical heat treatment apparatus includes a carrier conveying region in which a wafer-holding carrier called a FOUP is conveyed. The vertical heat treatment apparatus also includes a wafer conveying region in which wafers are transferred to a wafer boat as a substrate holding mechanism and are conveyed to a heat treatment furnace. A partition wall is formed between the carrier conveying region and the wafer conveying region. In order to prevent particles from adhering to the wafers during a heat treatment process, the cleanliness of the wafer conveying region is kept higher than that of the carrier conveying region.
A conveying gateway for the wafers is formed in the partition wall. The conveying gateway is opened and closed by an opening/closing door conforming to a FIMS (Front-Opening Interface Mechanical Standard). The opening/closing door is provided with a removal mechanism for removing a lid installed on the front surface of a carrier. In other words, the opening/closing door is required to open and close the lid to transfer the wafers between the inside of the carrier and the wafer conveying region, and to isolate the wafer conveying region from the carrier conveying region.
Semiconductor devices are highly functionalized and miniaturized, which tends to reduce the wiring line width and the design rule. It is therefore necessary to pay attention to particles even if the amount of the particles does not matter. In other words, there is a need to keep the wafer conveying region at a higher degree of cleanliness. From the viewpoint of reducing the manufacturing cost of semiconductor devices, it is advantageous to keep the apparatus installation environment, i.e., the carrier conveying region, at a low degree of cleanliness. However, if the degree of cleanliness in the carrier conveying region is low, it becomes easy for particles to adhere to a carrier. The opening/closing door arranged in the conveying gateway is opened toward the wafer conveying region while the lid of the carrier is held. Therefore, there is a possibility that the particles adhering to the lid may be taken into the wafer conveying region, thereby reducing the degree of cleanliness in the wafer conveying region.
In the related art, there is disclosed a device in which a nozzle for injecting a gas toward a lid of a carrier is installed at a partition wall to remove particles adhering to the lid. In light of the circumstances stated above, there exists a need for a device capable of more reliably removing particles adhering to a lid of a carrier.